1. Field of the Invention
The present invention relates to after-market vehicle-lowering steering knuckles (drop spindles), and more particularly to a newly designed drop spindle which is capable of supporting a large-bore xe2x80x9clivexe2x80x9d wheel hub and which can be used to lower a vehicle chassis.
2. Description of the Prior Art
A typical spindle (or steering knuckle) is a component of the front suspension of a vehicle, which attaches the wheel and brake assemblies to the vehicle, and allows the wheels to travel vertically (oust and rebound), turn, and rotate. The most common spindle bodies are of a cast metal configuration utilizing a press fit, metallic, machined, cylindrical shaft called a spindle pin to which the wheel bearings, brake components, and wheel are affixed. In particular, a wheel hub fits over the elongated spindle pin with bearing surfaces actually making contact with the pin. A vehicle wheel is, in turn, attached to the hub. This common type of pin and hub assembly is sometimes referred to in the industry as a xe2x80x9cdead hubxe2x80x9d.
For aesthetic purposes and for improved handling, it is common to lower the chassis of a vehicle closer to the ground by vertically repositioning the elongated spindle pin, steering arm and brake attachment features on the steering knuckle assembly. In this regard, numerous vehicle lowering steering knuckles (commonly known as xe2x80x9cdropxe2x80x9d spindles) have been developed in which the position of the spindle pin shaft has been vertically changed relative to the steering knuckle body, thereby raising the position of the vehicle wheels relative to the chassis which lowers the chassis closer to the ground. This is possible because most drop spindle bodies are large enough that there is considerable space within the body, often several inches, where the position of the elongated spindle pin can be established without affecting performance.
For a variety of reasons, the manufacturers of several light trucks have recently changed the design of the steering knuckles used on these vehicles to accommodate a different kind of wheel hub assembly. This has resulted in the replacement of the common spindle pin assembly with a much larger front spindle design which takes up virtually all of the space in the steering knuckle that was previously used to move the spindle pin in order to lower the vehicle.
In particular, in order to lower manufacturing costs, several new two-wheel (rear) drive (2WD) model trucks now utilize the same front spindle (cast) bodies as the fourwheel drive (4WD) models. The spindle bodies used for 4WD trucks usually incorporate some type of rotating joint assemblies, such as constant velocity (CV) joints, which allow the drive axles to move vertically with the front suspension while rotating. These rotating joints are typically attached to the spindle body by way of roller bearings. The drive axles are then attached to the brake and wheel assemblies through the use of wheel hubs and flanges.
However, the 2WD trucks do not incorporate these 4WD components. Instead, in 2WD trucks the manufacturers have recently, while using a common steering knuckle body, replaced the 4WD drive axle and CV Joint assemblies with bolt-in xe2x80x9clivexe2x80x9d spindle hubs to which the brake and wheel assemblies are attached. The term xe2x80x9clivexe2x80x9d hub implies that the hub assembly, to which the brake and wheel assemblies are attached, is made up of a short shaft that rotates within, and is affixed to roller bearings that are mounted within the hub bearing housing.
The hub bearing housing, in turn, is attached into the spindle body. This xe2x80x9clivexe2x80x9d hub simulates, and takes the place of the drive axle and rotating CV joint components of the 4WD models.
Significantly, the bolt-in xe2x80x9clivexe2x80x9d hub assembly requires a much larger bore diameter to be placed within the steering knuckle body, than that previously required for ae press-fit spindle pin. In addition, the bolts that attach the hub assembly to the spindle body have a set pattern which must be accommodated for. The large bore and the bolt-pattern require much more space than the press-in spindle pin designs. These differences in the design of these recent factory steering knuckles have taken away virtually all of the space previously available to accomplish the vehicle lowering function using existing drop spindle designs. Accordingly, it has heretofore not been considered possible to design after-market vehicle lowering drop spindles for such vehicles.
The present invention is a vehicle-lowering steering knuckle (drop spindle) designed for use with a large-bore xe2x80x9clivexe2x80x9d wheel hub to lower, a vehicle chassis. This is accomplished through the inversion and modification of the upper and lower ball joints on the factory steering knuckle, and a modification of the bolt assembly for attaching the wheel hub) assembly to the spindle. It is to be noted that the spindle design described herein may also be used to lower four-wheel drive trucks.
The recent factory steering knuckles for supporting xe2x80x9clivexe2x80x9d hubs include a lower ball-joint for attachment to a lower control arm, and an upper ball joint for attachment to an upper control arm of the vehicle. In the present invention, the lower ball-joint orientation is physically reversed, within the lower control arm, such that the factory-designed previously downward-facing stud faces upwards at a suitable angle in the present invention. The factory designed lower ball-joint is replaced with a new ball-joint specifically designed to be loaded in this new direction. The stud of the ball-joint is supported by a tab that is cast into the spindle body. The position of the tab is modified in the present invention, by being elevated relative to the xe2x80x9clivexe2x80x9d hub spindle centerline, and by being angularly oriented to receive the inverted ball joint stud. The inversion of the stud moves the ball attached thereto from above the tab to below it. The distance between the prior location of the ball-joint in the factory spindle (above the tab) and the position of the ball-joint in the present invention (below the tab) defines the amount by which the vehicle can be lowered using the present invention. The present invention raises the vehicle wheel position relative to the lower control arm, lowering the vehicle height by that same amount, relative to the ground. The new lower ball-joint tab configuration of the present invention is particularly effective in that it accomplishes the lowering of the vehicle within the limited space parameters of the recent factory xe2x80x9clivexe2x80x9d hub spindle designs.
The lower ball-joint housing has also been modified from the factory-designed compression structure to a new tension structure. In the factory design, the lower ball-joint was located above the tab, and a ball joint housing was fitted over it. This housing was attached to the lower control arm, and transmitted much of the weight of the vehicle to the spindle, thereby compressing the housing against the spherical faces of ball and socket joint. In the present invention, the lower ball-joint is located below the tab, and a modified housing is fitted around the ball. The housing is attached to the lower control arm, and transmits the weight of the vehicle to the spindle, thereby causing a pulling tension between housing and the ball joint.
The upper (follower) ball-joint is also inverted in the present invention. In order to maintain proper swing-angles, the factory supplied upper control arm is reversed so that the previously downward facing ball-joint stud is now reoriented upward. Proper ball-joint swing angles are defined such that, at normal static ride height, the suspension ball-joints are in a neutral position, allowing them maximum travel in both directions of suspension travel (joust and rebound). The factory-designed upper control arm is symmetrical, front-to back, allowing for such a reversed orientation. Because of this reorientation, the upper ball-joint tab, which i, cast into the spindle body, must also be reversed to receive the reoriented ball-joint stud. This reorientation is designed so as to provide the necessary strength of the casted spindle body, and to make possible the various machining operations, which are required to fasten the upper control arm ball-joint to the spindle body. Maintaining proper upper ball-joint swing-angles has always been a major obstacle in the design of after-market vehicle-lowering spindles. The present invention overcomes this difficult problem.
The ball of the inverted upper ball-joint of the present invention has been brought from a position above the upper tab to a position below said tab that is in close proximity with one of the bolt holes used for attaching the xe2x80x9clivexe2x80x9d hub assembly to the spindle body. In order to provide space for and to accommodate the new position of the upper ball joint and upper control arm, this bolt hole is counter bored in the present invention. The hut) assembly is then attached to the spindle body using a socket head fastener at this position.
It is therefore a primary object of the present invention to provide a vehicle-lowering steering knuckle (drop spindle) for use with xe2x80x9clivexe2x80x9d wheel hub assemblies.
It is also an important object of the present invention to provide an after-market drop spindle for lowering the chassis of a vehicle equipped with xe2x80x9clivexe2x80x9d wheel hub assemblies.
It is a further object of the present invention to provide a simple after-market drop spindle for lowering the chassis of a vehicle that is equipped with xe2x80x9clivexe2x80x9d wheel hub assemblies which drop spindle is capable of utilizing the factory provided upper and lower control arms.
It is another object of the present invention to provide a drop spindle apparatus for lowering the chassis of a vehicle equipped with a wheel hub assembly to which the brake and wheel assemblies are attached, said hub assembly being made up of a short shaft that rotates within, and is affixed to roller bearings that are mounted within the hub housing, which housing is, in turn, attached to the drop spindle body, the drop spindle also being capable of utilizing the factory provided upper and lower control arms.
Other objects of the invention will be apparent from the detailed descriptions and the claims herein.